Fusco Giuseppe, Minelli Alessandro
Department of Biology, University of Padova, Padova, Italy.
Front Cell Dev Biol. 2025 May 14;13:1585073. doi: 10.3389/fcell.2025.1585073. eCollection 2025.
One aspect under which an organism's life cycle can be considered complex is when the very same organism can undertake, or obligatorily undertakes, multiple developmental pathways. Examples are organisms with alternation of generations, like most plants, or organisms with reproductive and/or developmental options, like many marine invertebrates. With a broad taxonomic coverage across the eukaryotes, we survey these developmentally complex life cycles, presenting selected case studies to illustrate the relationships between the diverse developmental pathways within the same organism for what concerns morphogenesis and gene expression. We highlight the deep connections between the different types of cycles and show their relationship with phenotypic plasticity, sexual dimorphism and ecological adaptation. The collected materials and organized concepts can provide the basis for future investigations on the disparity of complex life cycles and their evolution across the tree of life.
生物体生命周期被认为复杂的一个方面是，同一生物体能够或必须经历多种发育途径。例如具有世代交替的生物体，如大多数植物，或具有生殖和/或发育选择的生物体，如许多海洋无脊椎动物。我们对真核生物进行了广泛的分类学覆盖，调查了这些发育复杂的生命周期，展示了选定的案例研究，以说明同一生物体内不同发育途径之间在形态发生和基因表达方面的关系。我们强调了不同类型周期之间的深层联系，并展示了它们与表型可塑性、性别二态性和生态适应的关系。收集的材料和整理的概念可为未来关于复杂生命周期的差异及其在生命之树上的进化的研究提供基础。
